The Harvard Extension School — a continuing education program at Harvard University — is offering a selection of course content previews for free, via
iTunes U.

iTunes U is an effort between Apple and various institutions of higher learning around the nation to publish course content online via iTunes. Some colleges and universities keep the content private specifically for their students, faculty and alumni; others, like the Harvard Extension School, make course content publicly available for free.

The iTunes U effort comprises video previews of 15 of the 50 distance education courses available at the Harvard Extension School this spring. Previews include computer science, management, environmental science, history and the liberal arts. Each preview is 10 to 15 minutes long, and audio of each complete two-hour introductory lecture is also available for download.